Portable photographic-dark-room lantern attachment.



G. F. HOLLAND. PORTABLE PHoToGRAPHlc DARK Room LANTERN ATTACHMENT.

Patented July 6, 1915.

APPLICATION FILED APR.22| |914.

COLUMBIA PLANDGRAPH CQAYASHINGTDN. D, C.

GORDON F. HOLLAND, F REVERE, MASSACHUSETTS.

PORTABLE PHOTOGRAPHIC-DARKROO1VI LANTERN ATTACHMENT.

Specification of Letters Patent.

Patented July 6, 1915.

Application filed April 22, 1914. Serial No. 833,778.

T0 all whom t may concern .Be it known that 1, GORDON F. HOLLAND, a citizen of the United States, residing at 113 Fernwood avenue, in Revere, in the county of Suffolk and State of Massachusetts, have invented certain new and useful improvements in Portable Photographic- Dark-Room Lantern Attachments, of which the following is a specification.

My invention is an attachment for electric light fixtures and it has for its object to provide a conveniently portable dark room lantern attachment adapted to be applied to an ordinary electric lamp such as is now in common use, and to be used in the development of photographicnegatives.

The invention consists of a lantern attachment for application to an electric lam comprising a lamp housing or boX ma e with a window provided with one or more panes of glass or the like to serve as a barrier for the actinic rays from the lamp, and means on said housing to provide for passing the bulb or globe of the lamp into the housing and for securing the latter to the lamp so that the light from the lamp can pass only through the window of the housm0'.

ther features of my invention are hereinafter pointed out.

ln the accompanying drawings -Figure 1 is a front elevation of my new lantern attachment for electric lamps. Fig. 2 is a plan view of the attachment shown in Fig. 1. Fig. 3 is a view, on a smaller scale, like Fig. 2 but showing the attachment open to receive the lamp within it. Fig. 4 is a section on line 4-4 of Fig. 1.

The housing of my new attachment comprises a more or less annular wall 1, made at one side with a window opening 2, having upon its interior three inwardly extending flanges 3 which are separated so as to provide two slideways between them in each of which is mounted a pane of glass 4. The panes 4 are colored as usual to serve as barriers tothe actinic rays from the lamp. Pivotally mounted at 5 upon the side wall 1 of the housing is a yoke shaped cover 6 for normally closing the upper ends of the slideways and for holding the glass plates in place. By swinging the cover 6 forward on pivots 5 the glass panes 4 can be removed when desired.

An end wall 7 permanently connected with the side wall 1 closes the outer end .of the housing, and in order to permit air to circulate freely into and out of the housing while the attachment is in use, so that the parts will not become too hot, this end wall 7 is formed near its middle with several per forations 8 opposite eachof which is an inwardly projecting inclined light barrier or shield 9. The perforations 8 surround a centrally disposed post 10 which supports a canopy 11 covering all of the perforations 8, said canopy being provided upon its periphery with a flange or rim'extending toward the end wall 7. The canopy 11 and shields 9 serve to prevent thepassage of light rays out through perforations 8. Post 10 and canopy 11 are fastened in place by means of a bolt as shown.

Fixed to the exterior of the wall 1 near the` inner end thereof is a pintle 13 upon which is pivotally mounted a pair of curved lamp engaging doors 14 and 15, each made upon one side with a perpendicular semi-cir cular liange 16 adapted to fit snugly against the inner end of the housing wall 1 when said doors occupy their closed positions. The meeting ends of the flange 16 are made with notches 17 which embrace a pin 1S when said doors occupy their closed positions, which serves to lock said doors against displacement away from the end of wall 1 while the attachment is in use.

In order to hold doors 14 and 15 in their closed positions l provide the flange 16 of one of said doors with a stud 19 to engage with a spring latch 2O riveted or otherwise secured to the flange of the other door. Each door 14 and 15 is made upon its inner periphery with a perpendicular semi-circnlar flange 21 adapted to embrace the socket 22 of the electric lamp 23, and in order that the attachment will be held rigidly to the socket 22 against endwise displacement thereon, each flange 21 is made upon its inner face with a recess 24 to engage the usual bead 25 with which lamps of this kind are ordinarily provided. As a further means for holding the two doors 14 and 15 together while the attachment is in use, one of the flanges 21 has a curved spring latch 26 fastened to it which springs around the other flange when the doors are closed.

To apply my attachment to a lamp the two doors 14 and 15 are swung into their open positions as shown in Fig. 3 so that the housing can be passed over the lamp, and then they are closed onto the lamp socket as indicated in Fig. 4, the latches 20 and 26 locking said doors in their closed positions and thereby firmly securing the attachment rmly to the lamp. j

In order to prevent the escape of light rays through the joints at the ends 'of the doors the latter are made slightly longer than 180o so that the ends thereof overlap when in theirclosed positions as shown in Fig. 2. My new lamp attachment is conveniently storedor transported and can be quickly Copies of this `patelt may be `obtained Ifor five cents each, by addressing the lamp supported housing made with a window and a doorway, the latter being of a size to permit of the passage therethrough of an electric lamp bulb; a pane of colored transparent material removably mounted in y said window; Ventilating openings in said housing; a shield covering said Ventilating openings so as to prevent the escape of light rays; a pair of doors for said doorway permanently pivoted to said housing so as to close toward each other around the lamp and interlock with the latter to fasten thc attachment to said lamp with the bulb of the latter held out of contact with the housing and the latter held against rocking on f the lamp, the meeting ends of said doors overlapping to close the joints between the same, and means for holding said doors in their closed lamp engaging position.

In testimony whereorl I have affixed my signature, in presence of two witnesses.

GORDON F. HOLLAND.

IVitnesses:

MARY E. MINTON,

Gnoncn F. MoUL'roN.

Commissioner of Patents,

Washington, D. 1C.

/i fi 

